The Ministry of Science and Technology has recommended the accelerated adoption of steel-slag-based road construction technology across India, particularly for hilly and difficult terrains, positioning the material as a durable and cost-efficient alternative to conventional natural aggregates, according to reporting by Change Started and the Economic Times Infrastructure desk.
Steel slag is a byproduct of the steel manufacturing process. According to the Central Road Research Institute, roads constructed using steel-slag aggregates demonstrate compressive strength exceeding 120 megapascals and abrasion resistance approximately 22% higher than traditional natural aggregates, with significantly lower lifecycle maintenance costs, according to the research documents. These figures are attributed to CRRI and have not been independently verified against a primary CRRI publication for this article.
From Pilot to National Scale
Pilot projects using steel-slag road technology began approximately two years ago in Gujarat and Arunachal Pradesh, according to the research documents. The technology is now being deployed in Karnataka, Uttar Pradesh, Assam, and Andhra Pradesh. In Andhra Pradesh, a pilot project named Ecofix is testing a composite mixture of steel slag and tar for pothole repairs near the state secretariat, according to ET Infra. The Technology Development Board has signed a commercial agreement with Ramuka Global Ecowork for the production of repair mixes; a new steel and iron slag processing facility is expected to be operational by late 2027, according to the research documents.
A two-day national workshop is scheduled for next week in Jammu and Kashmir to orient engineers on the application of this technology in Himalayan terrain conditions, according to the research documents. The initiative aligns with the government’s Waste-to-Wealth programme, which seeks to convert industrial byproducts into infrastructure inputs.
Global slag usage in road base applications stands at approximately 80 million tonnes annually, according to industry data cited in the research documents. India’s projected steel slag generation by 2030 is estimated at 60 million tonnes, according to the same sources, though these projections carry inherent uncertainty.
